This invention relates generally to improved grinders. More particularly, but not by way of limitation, this invention relates to an improved grinder and to wheel guards therefor wherein loads imposed on the wheel guards are transferred to the grinder housing.
Grinder wheel guards are provided in an effort to prevent injury to the operator of the grinder or to persons in the nearby vicinity in the event that a grinder wheel disintegrates during use. As is well known, grinder wheels rotate at relatively high speeds and thus disintegration of the wheel releases a considerable amount of energy which can cause severe damage or injury.
Wheel guards utilized on grinders in the past have been reasonably successful, but they must be made relatively light and yet sufficiently strong to absorb all of the energy that is dissipated. One of the weaker structural parts of grinding wheel guards has been in the method of attachment to the grinder housing. Most often, the grinder wheel guard is simply provided with an opening that fits around the shaft and the guard is then attached to the housing by means of threaded fasteners or the like. When a load is imposed on the wheel guard, the load is transferred directly into the threaded fasteners which may shear permitting the wheel guard to rotate and either become dislodged from the grinder or rotated about the shaft to a position wherein the operator will be exposed to fragments from the grinding wheel.
U.S. Pat. Nos. 4,059,930 issued Nov. 29, 1977 to Lorenzo Ercole Alessio and 4,103,460 issued Aug. 1, 1978 to John P. Law, each illustrates a grinder and grinder wheel guard combinations. Each of the guards that are described in the patents incorporates certain safety features, but each is attached to the grinder housing by fasteners that are subject to being sheared in the case of loads being imposed on the guard.
It is the object of this invention to provide an improved grinder and wheel guards therefor, wherein loads imposed on the wheel guard are transferred directly to the grinder housing.